Modern day integrated chips are formed by executing a complex fabrication process on a semiconductor body. The complex fabrication process often comprises implanting dopants into the semiconductor body and then building one processing layer on top of another to form devices within the semiconductor body and metallization layers above the devices. To selectively form the processing layers in a desired location, the processing layers are often deposited, masked, and then etched in unmasked areas using a dry or plasma etch.
To achieve good etching results an end point detector is located within an etch processing chamber. The end point detector is configured to determine when a processing layer is completely removed from the semiconductor body. This allows for complete removal of one processing layer without damaging an underlying processing layer.